Immunohistochemical studies of Interleukin-8 and Tumor necrosis factor-alpha on psoriatic lesions

Won, Duck Hwan; Kim, Young Keun; Choi, Gwang Sung

Abstract

BACKGROUND: Psoriasis is a chronic skin disease characterized histologically by prominent keratinocyte hyperplasia and an early inflammatory cell infiltrate. However, the pathogenesis is not fully understood yet. Recently, there has been growing interest in the probable role of a T cell mediated immune response in the pathogenesis. Especially, cytokine network involved in psoriasis has been studied.
OBJECTIVE
This study was done to investigate the role of Interleukin-8(IL-8) and its inducer, Tumor necrosis factor-alpha(TNF-alpha) for pathogenesis of psoriasis.
METHODS
We performed immunohistochemical staining using antibodies for IL-8 and TNF-alpha in frozen skin samples of 14 psoriatic patients who had not been treated for psoriatic lesion for 1 month and 3 normal skin samples as controls.
RESULTS
There was no detectable discrete immunoreactivity for either TNF-alpha and IL-8 in epidermis and dermis of normal controls. In psoriatic lesions, the expression of TNF-alpha was found in dermal cells within the papillary dermis, particularly around blood vessels. The expression of IL-8 was presented on suprabasal keratinocytes above TNF-alpha-positive dermal tissue.
CONCLUSION
Our results strongly suggest that histologic expression and functional interaction between IL-8 and its inducer, TNF-alpha have significant roles in the pathogenesis of psoriasis.